If cane sugar is the worst “natural” sweetener, why was diabetes so rare before the sudden increase of diabetes in the 20th century?

Question

I know around the middle of the 20th century vegetable oils, synthetic sweetener became a thing. But statistic wise doesn’t make sense, even if before it caused tooth problems, but not diabetes.

In: Biology

Answer 1

Mass production of processed foods, which are loaded with sugar, ramped up in the late 20th and hasn’t slowed.

Limited understanding of diabetes and lack of reliable insulin sources means anyone that got diabetes would’ve likely died, making it less likely to pass on.